Method of engraving copper rolls for printing fabrics.



W. H. HOPE.

METHOD 0f ENGRAVING COPPER ROLLS FOR PRINTING FABRICS. APPLICATION FILED IuIIe 4. IsII.

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vvlLLfIAn; nornonrnovnnivcn, RHODE ISLAND'. i'

Q'. METHoDjoF-nNeRAvING COPPER noLLsroR PRINTINGV FABRICS.

ssecimioatf Lettertsra'tent Patented lVKIa1.'V1I9,'191S.

. the etching.` f

itfknoivn :that I ldlrnnniinl. Horn, a citiZen of the,k United f States, .residingj-at Providence, in the county of ,Providence and State. of Rhodelsl and', have invented a nen7 and useful,Improvement in 1 Methods ,ofI En graving kCopper Rolls for l Printing Fabrics, of which .the following, is, afspecification.``

This invention relates to certain nevv and useful :improvements finv` ,the method lofy engraving copperlrolls for printing" fabrics, and more? `particularly to v the transferring of the design bylral stylus and y cutter or graver l proportionate in; size `to 'the a desired vvidth of Yundercut;produced ,on fthe roll'by The .invention Vresides linfthe method of engraving by a; stylus having ,a flat .edgeinstead of theusual.pointedgtool,

,said liatedgebeing proportionate in size to the desired Width of they undercut thatis to be. produ ced by the `acid etching, and Va graver also having fan edge of ysuch Width as yis necessary.. for fthe removal of the varnish .from `the lroll t0 permit of the action ofthe acid on'saidcoppenfroll ,for causingvthe `proper undercut.k

1 VThe invention Waite bam: @deemed wherein-f Figure 1 illustratesa design shOWlV in the colorsy desired yon' a Hat sheetmetal plate, usually.,andpreferablyl 'r/.inclfd by reference tothe accompanying Fig. .2 is a frgrnentaryfportionof acopper roll, lshowing ajprtion A of kthe brown color part ofthe design, Engraved thereon.

i Fig. ,3 .isv a siniil'ar view o-f aroll bearing the blue color part ofthe design.`

. Fig. 4f isa-.viewoffa roll? havlngfa por- .en ofthe rea @10eme ,or the designengravedthereonff,.,y

-F1g.` 5 isjan enlargedsquaredwportionlof y,any `one ofy thejl colors e' shoWIifbyj itself for iease infdescribingthe method;` 45

M Fig. ',7 avlikeillustrationlof'thegraver,

Fig,v 8 shoivsf'in solid lines `the portion'of varnishrernoved from v thef|` cop-per@ roll by y the `graver tracing-the lsquareshown in Fig. l5. Withfthestylus, the dotted portionr'of Sad' Fis 8 representingtheextent, Of' undercutvofthe acid in the etching process'. Referring moreparticularly to the drayving,'the numeral" 1 indicates either a vportion f ofva design or-ithe comple'teldesign itself which is painted'or otherwise indicatedon a flat' sheetmetalplate, said plate preferably being f. rzinc and said colors of tliegdesign preferably-being those in' 'which `the finished fabricflvvill be printed. This plate, bearing i the design, is ruled``withfa` numb/erf offhori- :zontal and perpendicular'lines l to repre,- sentthe desired mesh orY block ofthe'fiveave to be reproduced, the drawing being divided into knine'lolocks tothe inch although on' an enlarged scale.`

,. vThe usual method of engraving print rolls employs a y pointed stylus but With vsuch tool @or instrument itk is limpossible to determine theundercut oflthejacid letching..',"lhisfil/ilvention lembodies la at edged stylus/2 anda ing anarrovv stylus isrequired andfor relative` deep etching a comparatively Wide or broadfstyluslis necessitated. l The' degreeof undercut isk previously determined soA that fisy readily apparent.` that lfor a shallovvfetchthe required stylus may be selected,tle

yWidthof thestvlusbeing twice the `amount ofundercut.k Therefore, should ai graverbe VVpositioned for `moving in. unison with the `stylus and the latter f bel shifted' laterally' or of said stylus touchesy one7 border line of IAa pattern to aposition in Which the opposite side" of the stylus vtouches the opposite" border line, ,the totalk travel of` the 4 stylus y,will

`edgevvise fro'nra' positionin which one side i .beV the, full Width of rthe pattern lessv the fvvidth ofthe stylusle'dge. Consequentlv, the yextent ofrmovement ofthe graverfvvill'fbe accordingly' great, less ythe `.Width of the stylus which provides forthe necessary undercut of the etching fluid. `T0 obtain ther` desired'space ati eachend ofthe lil-nit of 015- eration lof the graver, to Aaccommodateffor the underuttingof the acid in bothv direc- ',tions, litfis essential that thelatter; be 'started at a' point midway' of the Width ofithestyms.

For ease vin relatively pcrisitioningthestylus land graver, theformerA is provided avv-ith `a centerline kk(Fig. 6v),k andthe graver may then be @1in-@d with the .Sanesthat mastering and linishing points of the graver-Willbe one-half the Width'ofthe-stylus inwardly from the extreme reach of said stylus. Therefore, the acid 'undercut or etching Will be equal to One half the Width of the stylus. The Width of the face of the graver is equal to the Width oit' the pattern transferred to the roll less twice the amount of the acid undercut in order to produce the same Width of border around the block design for acid under etching. v

As illustrative of the present meth'od, Fig. 5 represents av single square block of color of the design taken from the design plate 1. The stylusis then placedon the top edge of the block or' color with its edge 4 on the left hand border 5 of-saidblock, andthe graver 3 is dropped onto the roll 6 (Figs. 2, 3 anda), care havingbeen taken to set the left edge of the graver on the left border of theparticular design block. The stylus iswmoved along thetop line tothe ,broken line, position 7, Fig.. 6, or until 4rthe right edgel 8V of the stylus registersivith the right hand border of the square. This movement, through the pantograph mechanism, effects movement of the graver moving thelatter to the dotted position 9, Fig. 7. Thus referring to Figs. 5 and 8 with the edge of the stylusbeing 'moved longitudinally along the upper line of block 5, the graver Will move broadwise. The extent of movement re'- .quired to shift the stylus from. the position in Which itsleft end ltouchesthe border of square 5 to the position in which the right end touches the rightborder of said square is indicated kby thetop line of's'quare 10 land a.A vertical side of the latter designates the Width of the face of the graver. This operation Will remove varnish from the roll as indicated at 10, thedilierence in size between the square 10 and that shown in Fig. being equal to the extent of undercut of the acid, this being indicatedA bythe dotted square 11.y .Consequently should acid ybe applied to the roll,.the undercut of the metal would besuch Las to produce a square, as large-as the dotted lines 11` or aslarge as that of Fig. 5. *l

A stylus and graver :of proportionate size will bevused, depending upon the fabric to be printed,to produce a depth of etching in the roll that Will carry theproper -amount of color for suchprinting. The Width. of thestylus is'alvvays proportioned inversely to the ividthzof vthe graver and as'the action lof the stylus is on the top edge of the color, theroll'on which the graveroperates will have the, edge .of the graver -represent the top l'line of thecolor, sothat the Wider the faceof thegraver, the narrower the faceofthe stylus will be andthe greater the vundercut. This relation between the Width of theiace pf thegraver and ,thaty of the' stylus is necessary in order to produce the same wid-thofborder around the block design for acid-underV etching. y

The rolls in Figs. 2, 3 and 11 represent individual rolls for-eaclrcolor;the' roll for the brovvn color being depicted in Fig. 2, that for theblue color being shown inrFig."3,-and that orthe red color being disclosed in Fig. 4. The colors; or their squares or configurations, are depicted before the application ofthe etching acid so' thatv said conigurations' correspond ,to the. smaller square ,10: in F ig'. 8, being lessth'an' the true size.

Thu's, byemploying. the stylus and graver proportionateto the undercut'd'esired, which depends`v upon' the' fabric ,tvofb'e printed and the Color tot be carried by the'. roll", it Will be unnecessary to constantly determine the'eXr-l tent kof undercut; no eXp'ert'help' or operative will be required, and the 4same unvarying and perfect blending of the colors With no ir; regular or overlapping edges Will result.

In practice, the graver or cutter isset Vat right angles to the stylus and secured-` its shank in a suitable holdengsuchas' the usual diamond bar, and the stylusfis mounted in thehfand piecey that moves over the design oi'pattern.

Having thus described my inventiomwhiat 1 claim' as new and desire to'secure'by Let'- ters Patent is-l l l.v The method of engraving copper rolls for printingrfabric, consisting in dividing the pattern into blocks of colors, providing fla` t, edged stylus and a graver havingan edge of a Width inversely proportionateV to thewidthof the stylus disposing the graver edge at right angles to the stylus edge, and moving the edgeI along the top line of Va block of the pattern, `,engraving the individual. colors on separate rolls.'

2. The method of engraving rolls. consisting. in dividing the pattern' into' blocks of individual colors, providing a stylus and graver, each with a flat edge,.arran^g`i`ng the graver edge at right' angles to `the stylus edge, and moving the-latter along a border line of a ypattern block.

3..,The method .of engraving rolls con sisting in dividing the pattern into blocks of individual colors, providing the stylus and gravereach With afflat edge, the Wider the stylus edge the narrower the graver ledge, Yarrangingmtlile stylus andrgraver so..

that the latter will operate broadside Ona roll on movementof the stylus,y edgellongitudinally, and moving the stylus 'edge along `a borderline of a ypattern block. 1

4. Thel method of engraving rolls con sisting in tracingedgewise a flat edge stylus equal inwidthtotwice the amountof the undercuttingof theacid, and ,moving a -iiat edge graver broadtvis'e;

l `,5. The method. of, engraving;rolls,'con

SStills .miradasabrdrlineof a Pattern with a stylus having an edge equal to double the width of the undercut of the acid, providing a graver equal in width to the design less twice the undercut, and moving the stylus edgewise and the graver broadwise.

6. The method of engraving consisting in tracing the border of a color with a stylus having a width equal to twice the amount of the underetching and moving a graver l0 broadwise, said graver being equal 1n width to the design less twice the amount of the underetching.

In testimony whereof I have signed `my naine to this specification in the presence of two subscribing witnesses. I VILLIAM H. HOPE.

VVituesses ADA E. .HAGERTY, J. A. MILLER.

opies ofthi: patent may be obtained for ve cents each, by addressing the Commissioner of Patents.

` Washington, D. G. 

